Patents by Inventor Henricus C. J. Krekels

Henricus C. J. Krekels has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Distributed feedback laser with anti-reflection layer
    Patent number: 4833684
    Abstract: A semiconductor laser of the distributed feedback (DFB or DBR) type is bounded in the longitudinal direction by end surfaces at right angles to the active region and at least one of these end faces is provided with an anti-reflection layer in order to suppress Fabry-Perot modes. In order to obtain an optimum effect, an anti-reflection layer of hafnium oxide is used. The invention is used with great advantage in lasers of the DCPBH (Double Channel Planar Buried Hetero-structure) type.
    Type: Grant
    Filed: November 1, 1988
    Date of Patent: May 23, 1989
    Assignee: U.S. Philips Corp.
    Inventors: Henricus C. J. Krekels, Pieter I. Kuindersma